If you want content to appear "outside" the body of the Zen Cart-generated site, you'll have to use positioning.
In terms of "where" to put the code, why not just put it in a new left sidebox?
the "best" place depends on what code you finally use to display it. What you are using right now is ... well ... not good.
If you're bent on having it outside the store area, the journey ahead will be interesting...



